On a dark winter day in 1981, Roger Hill sat in a windowless cubby in the dungeons of Massachusetts General Hospital, in Boston, designing a computer model of blood flow and pressure inside the lung. He was a Harvard postdoc, with a Ph.D. in engineering from Oxford, researching pulmonary artery function. But what he really wanted to do was build gadgets.
Harvard professor and anesthesiologist Warren Zapol stopped by. Zapol was studying patients who survive oxygen deprivation and was also trying to understand sudden infant death syndrome, in which a baby stops breathing for no apparent reason. He thought that both situations might be related to the way marine mammals’ bodily functions change when they dive. He asked Hill if he could build a gizmo that could be attached to the back of a seal and record depth and heart rate and take blood samples while the seal dived into the water.
That question changed Hill's life. Six months later, he was in Antarctica, supergluing epoxy-encased circuit boards to the backs of Weddell seals.
Today, Hill is the go-to guy for marine animal researchers around the world. He has designed computers that calculate the migration path of elephant seals by measuring sunrise and sunset; devices that track walruses across ice and through water; and tags that record the travels of great white sharks and the migration of tuna. One of his lightweight dive recorders determined that emperor penguins can dive 600 meters, far deeper than anyone ever thought. These days, Hill is back in Antarctica, testing instruments he designed to study how aging affects Weddell seals.
Back to 1981: Hill and a technician built their first seal computer around the just-introduced NSC800, an early CMOS microprocessor. The device controlled a peristaltic blood pump that would function down to 1000 meters, and sensors that measured the animal's heart rate, core body temperature, and snippets of EKG signals. A fiber-optic cable let researchers download recorded data with the package still attached to the seal.
The first prototype worked—until Hill was encapsulating it in a thick coating of epoxy and glass beads (to make it neutrally buoyant), which caused it to overheat and then explode. There was no time to build a second prototype before his scheduled departure for McMurdo Station, in Antarctica, so he took circuit boards, epoxy, and bits and pieces of electronics with him. At McMurdo, he discovered that pouring the epoxy in layers instead of as a block eliminated the overheating.
While Hill assembled his gizmos, the other members of the research team selected a spot on the ice and set up the field camp, complete with a seal-size hole. Hill, Zapol, and the rest then went out to a seal colony, selected a seal, and herded it onto a sled. (Antarctic seals have no land-based predators, so they are not afraid of people.) They then drove the sled to their camp, where doctors anesthetized the seal and inserted a catheter through an artery and into the aorta. At the same time, Hill glued a neoprene pad onto the seal's back and attached the computer (about the size of a paperback book), the battery pack (a little larger than a deck of cards), and the blood-sampling equipment (slightly smaller than a can of soda) by screwing them into mounts on the neoprene.
Once the seal woke up, the group brought it over to the hole in the ice. The seal dived right in. When it resurfaced 20 minutes later, Hill plugged the device's fiber-optic cable into his Zenith Z80 desktop computer, downloaded the data, retrieved the blood sample collected mid-dive, set up the parameters for the next dive, and waited for the seal to dive again. The group repeated this process for a few days, then removed the catheter and gear, took the seal back to its original capture point, and picked up a new seal.
The research results were astonishing. It turned out that the concentration of red blood cells rose steadily during the first 20 minutes of a seal's dive; the researchers could only guess where the cells were coming from. A few years later, Zapol confirmed that the seal's spleen releases oxygenated blood cells as needed, providing new insight into that previously mysterious organ.
Meanwhile, Hill was hooked: ”It was way more fun than doing work on pulmonary arteries of sick patients.” He also loved the work because, he says, ”I like getting my hands dirty. I liked the technological challenge.” And spending long hours outdoors sure beats sitting in a windowless basement—this is a guy who, during high school and college, would regularly go off on two-week hikes through the English countryside or remote areas of Lapland.
He even met the woman who is now his wife, Suzanne Braun (now Suzanne Hill), on that first trip to Antarctica, where she was doing doctoral research on the maternal bond between Weddell seals and their pups. But she had no interest in the self-described nerd. ”She took up with a helicopter pilot,” Hill recalls.
The next year, though, Hill prepared to wow her. Despite his limited baggage allowance, he packed a tuxedo. Then, for the big Halloween party at McMurdo Station, Hill added fins he had borrowed from a dive locker, a black balaclava, goggles, and a funnel liberated from the biology lab; with bits of yellow tape in strategic places, he became a penguin.
The strategy worked. Braun finally noticed him, and this past October they celebrated their 25th anniversary—in Antarctica, of course.
Hill continued to build gadgets for Zapol until 1985, when the funding ran out and Hill reluctantly went back to his research on the human lung. But marine researchers who'd heard about Hill's seal work began contacting him to talk about devices that they dreamed about. For one Seattle-based researcher, he built a data recorder that measured dive depths and dive durations for freely swimming seals. The researcher, John Bengtson, was thrilled.
Emboldened by this success, Hill quit his Harvard post in early 1987, moved to Seattle, and started Wildlife Computers, in Redmond, Wash., to work on marine devices full-time. In the early days, the company worked under contract to marine researchers; later, it began building off-the-shelf products, like US $3500 fish tags that record data for a preprogrammed time period (as long as a year) before popping up to the surface to transmit the collected data via satellite. Times were lean for a while, but now Wildlife Computers is a multimillion-dollar business with 28 employees.
And that's about as big as Hill wants it. He still spends most of his day writing software or designing circuit boards, and he loves the variety. ”One morning I'm trying to figure out how to make a gizmo that's going to cut the line that connects the towed tag to the animal, so that if the animal dives too deep, the tag is released and doesn't get crushed,” he says. ”That afternoon I'm discussing code. And in the middle of that I'm laying out the design of a new tag.” On occasion, he still joins research teams in Antarctica or other remote posts.
At this point, Hill can direct his destiny. ”We only make instruments that further the understanding of animals to help with their conservation,” he says. ”I have a complete absence of guilt about everything I do,” he says. And he plans to keep it that way.
To Probe Further
Click here for the Marches With Penguins Slideshow